Accuracy and Reliability of MRI Reports in Diagnosing the Symptomatic Knee in Patients Who Had Bilateral MRI

Document Type : RESEARCH PAPER


1 Surgery and perioperative care, Dell Medical School -- The University of Texas at Austin

2 Radboud university medical center, Radboud Institute for Health Sciences, Department of Surgery, Nijmegen, the Netherlands

3 Orthopaedic surgery, Amsterdam University Medical Center, Amsterdam, The Netherlands

4 Occupational Medicine & Pain Management, OccMD Group, Texas Health Dallas, Dallas, Texas, USA

5 Dell Medical School -- The University of Texas at Austin


Background: Newly symptomatic chronic musculoskeletal illness is often misinterpreted as new pathology, particularly 
when symptoms are first noticed after a noxious event. In this study, we were interested in the accuracy and reliability of 
identifying the symptomatic knee based on bilateral MRI reports.
Methods: We selected a consecutive sample of 30 occupational injury claimants, presenting with unilateral knee 
symptoms who had bilateral MRI on the same date. A group of blinded musculoskeletal radiologists dictated diagnostic 
reports, and all members of the Science of Variation Group (SOVG) were asked to indicate the symptomatic side based 
on the blinded reports. We compared diagnostic accuracy in a multilevel mixed-effects logistic regression model, and 
calculated interobserver agreement using Fleiss’ kappa. 
Results: Seventy-six surgeons completed the survey. The sensitivity of diagnosing the symptomatic side was 63%, 
the specificity was 58%, the positive predictive value was 70%, and the negative predictive value was 51%. There was 
slight agreement among observers (kappa= 0.17). Case descriptions did not improve diagnostic accuracy (Odds Ratio: 
1.04; 95% CI: 0.87 to 1.3; P=0.65).
Conclusion: Identifying the more symptomatic knee in adults based on MRI is unreliable and has limited accuracy, with or 
without information about demographics and mechanism of injury. With a dispute concerning the extent of the injury to a knee 
in a litigious, medico-legal setting such as Workers’ Compensation, consideration should be given to obtaining a comparison 
MRI of the uninjured, asymptomatic extremity.
Level of evidence: II


Main Subjects

Volume 11, Issue 1
January 2023
Pages 23-28
  • Receive Date: 19 October 2020
  • Revise Date: 08 September 2022
  • Accept Date: 11 September 2022
  • First Publish Date: 01 January 2023